Name or state the following with reference to the element of the first three periods of the periodic table.
Alkaline earth metal in Period 3.

Explanation

To solve the question about identifying the alkaline earth metal in Period 3 of the periodic table, follow these steps:

### Step-by-Step Solution:

1. **Understand the Periodic Table Structure**:
- The periodic table is organized into periods (horizontal rows) and groups (vertical columns). The first three periods contain elements that are arranged according to their atomic number.

2. **Identify the Groups**:
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